This paint sprayer could be useful for both big and small projects. There's no cord to restrict you, just make sure you've charged the battery.
From Amazon
Einhell Power X-Change 18V Cordless Fence & Decking Paint Sprayer - Effortless And Fast Painting Of Fences, Sheds, Decking & Garden Furniture - TC-SY 18/60 Li Solo Spray Gun (Battery Not Included)
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